JP2015519162A - Electrosurgical instruments and systems - Google Patents

Abstract

The hand-held electrosurgical instrument includes a handpiece (2) and an electrode assembly (3). The electrode assembly includes one or more electrodes (12), (13) and connectors (8), (9) that allow the electrode assembly to be attached to and detached from the handpiece. The handpiece includes a battery (4), an RF oscillator circuit (5) that generates a radio frequency output, and switching means (7) operable by a user of the electrosurgical instrument. A control circuit (6) is provided to control the RF output, receives signals from the switching means (7), and accordingly supplies one or more RF outputs to the electrode assembly (3). The electrode assembly (3) includes components (14), (21) that can be modulated so that the RF power reaching one or more electrodes (12), (13) is an appropriate RF power at one or more electrodes. ).

Description

  The present invention relates to an electrosurgical instrument and electrosurgical system for use in tissue treatment. Such systems are used for endoscopic or “keyhole” surgery (“keyhole” surgery) as well as for the more traditional “direct-viewing” surgery (“open” surgery).

  Many electrosurgical systems have some form of identification system. When an electrosurgical instrument is connected to an electrosurgical power generator, the power generator detects which type of instrument is currently present and in some cases is suitable for that particular instrument or instrument type, for example, power and voltage settings The following settings can be used. The Applicant's US Pat. No. 6,074,386 (see US Pat. No. 6,077,849) is an example of such an identification system, although other types are known.

  The present invention seeks to provide an alternative to such an identification system. It enables a power generator used as part of an electrosurgical system to be substantially simplified. This is particularly important when trying to provide a hand-held electrosurgical instrument.

The hand-held electrosurgical instrument includes a hand piece and an electrode assembly. The electrode assembly includes one or more electrodes and a connector that can be attached to and detached from the electrode assembly with respect to the handpiece,
a) a battery;
b) an RF oscillator circuit for generating radio frequency output;
c) switching means operable by a user of the electrosurgical instrument;
d) a control circuit for controlling the radio frequency output (also referred to as RF output), wherein the control circuit receives a signal from the switching means and can supply one or more RF outputs to the electrode assembly accordingly. Including;
The electrode assembly includes components that can capture the RF power coming out of the handpiece and change the RF power reaching the one or more electrodes to be different from the RF power coming out of the handpiece.

  By including the change imparting component in the electrode assembly, the control circuitry within the handpiece can be simplified. For example, the control circuit need not include circuitry to generate a wide range of different RF outputs. The change imparting component can customize the electrosurgical output before the electrosurgical output from the handpiece is transmitted to the electrode assembly. Thus, the output of the handpiece is customized to make the output at the electrode assembly suitable for a particular situation, depending on the type of instrument and the particular process being performed.

  As noted above, the handpiece need not be able to generate a wide range of electrosurgical output to cover various electrode assemblies and processes. The handpiece simply produces a base electrosurgical output that is modified by a change-providing component in the electrode assembly so that the selected output is produced. I think the handpiece is so simple that it always produces a single RF output when activated, and the electrode assembly changes its RF output to produce the desired RF output with one or more electrodes. .

In a preferred embodiment, the component capable of changing the RF output reaching the one or more electrodes comprises a transformer including at least a primary coil and a secondary coil.
Alternatively, the handpiece includes a primary transformer coil, the electrode assembly includes a secondary transformer coil, and when the electrode assembly is connected to the handpiece, the primary and secondary coils are connected , Acting as a transformer capable of changing the RF output from the RF oscillation circuit.

  Thus, even if the handpiece can produce a single RF output, the secondary coil changes the output to produce an electrosurgical output suitable for the associated electrode assembly. It will be appreciated that the handpiece can be used with a variety of different electrode assemblies having different electrodes or intended for different electrosurgical processes. Each type of electrode assembly includes a secondary coil with a specific number of turns and alters the output of the handpiece to an output suitable for that specific electrode assembly.

In a preferred embodiment, the electrode assembly includes a passive electrical component having a finite non-zero value parameter, wherein the passive electrical component varies the RF power reaching the one or more electrodes to provide the one or more passive components. A desired RF output is generated at the electrode.
Preferably, the passive electrical component operates in conjunction with the control circuit to change the RF output reaching the one or more electrodes.
Passive electrical components are typically resistors or other impedances. However, reactive components such as capacitors and inductors may be used depending on the required conversion from the signal supplied by the handpiece to the signal required by the end effector. In addition, a network of components may be used to provide an appropriate transfer function.

  For the first type of electrode assembly (eg, a cutting needle), the value of the resistor is such that it changes or controls the output of the handheld instrument to generate an appropriate cutting voltage. In the case of the second type of electrode assembly (eg, a pair of coagulation jaws), the resistor values are different to produce another output that is more suitable for tissue coagulation.

  The change imparting component in the electrode assembly includes a plurality of parameters related to output from the handpiece, including RF energy power, voltage or current, RF energy frequency, or RF energy type (continuous burst or pulsed burst). It is preferable that any one or more of them can be changed. By having this capability in the electrode assembly, the handpiece can substantially simplify its structure and design.

  In another aspect of the invention, an electrosurgical instrument in one embodiment includes a handpiece and an electrode assembly releasably connectable to the handpiece, the handpiece comprising an RF signal source, and the handpiece. A control switch operable by a user to control a radio frequency (RF) signal driven by the RF signal source and the electrode assembly is applied when an RF therapy signal is applied to tissue One or more electrodes forming an end effector for treatment of tissue, and configured to receive the radio frequency signal from the handpiece and convert it to the RF treatment signal required by the end effector. Circuit configuration.

  According to the above aspect, as described above, since the handpiece is not required to generate a plurality of different waveforms, a very simple design is possible. Instead, the generation of a specific waveform is left to a component in the electrode assembly, which identifies the general or standard waveform received from the handpiece that is required by a particular type of end effector in the electrode assembly. Adapted to convert to waveform.

  For example, the RF therapy signal generated by a component in the electrode assembly is an RF cutting signal when the end effector is a cutting instrument and an RF coagulation signal when the end effector is a coagulating instrument.

  In one embodiment, the circuit configuration comprises at least a secondary coil of a transformer. The transformer is configured to change the RF signal output from the handpiece. In particular, the handpiece may comprise a transformer primary coil, the primary coil configured to receive a signal from an RF signal source and generate an output RF signal from the handpiece. In this way, the handpiece and the electrode assembly cooperate to generate an RF therapy signal from the RF signal source.

  In an alternative embodiment, the circuitry further comprises a transformer primary coil, the primary coil configured to receive an output RF signal from the handpiece. In such embodiments, all signal conversions from general or standard waveforms to RF therapy signals will be performed by the electrode assembly.

  In one embodiment, the circuit configuration comprises an electrical network configured to convert a radio frequency signal to an RF therapy signal. Preferably, the electrical network is a passive network with one or more resistances, impedances and / or reactances. Passive networks are easier to implement and operate.

The invention further extends to an electrosurgical system comprising a handpiece and a plurality of electrode assemblies.
The electrode assembly is at least a first type or a second type of electrode assembly, each including one or more electrodes, removably connectable to the handpiece, the handpiece comprising:
a) a battery;
b) an RF oscillator circuit for generating radio frequency output;
c) switching means operable by a user of the electrosurgical instrument;
d) a control circuit for controlling the RF output, wherein the control circuit receives a signal from the switching means and can supply one or more radio frequency outputs (also referred to as RF outputs) to the electrode assembly accordingly. Preparation;
The first type of electrode assembly includes a first part, the second type of electrode assembly includes a second part, and the first and second parts are RF emanating from the handpiece. The output can be varied so that the RF power reaching one or more electrodes of the first type electrode assembly is different from the RF power reaching one or more electrodes of the second type electrode assembly.

The invention will now be described in detail by way of example only with reference to the accompanying drawings in which:
1 is a schematic view of a hand-held electrosurgical instrument according to the present invention. FIG. FIG. 6 is a schematic view of another handheld electrosurgical instrument according to the present invention. FIG. 3 is a schematic diagram of a control circuit of the hand-held electrosurgical instrument of FIGS. 1 and 2. It is a figure of the waveform produced | generated by the control circuit of FIG. FIG. 4 is a diagram of another waveform generated by the control circuit of FIG. 3. It is the schematic of the primary coil and the secondary coil which are the components of the hand-held surgical instrument of FIG. 1 and FIG. FIG. 3 is a schematic view of another primary coil and secondary coil that are components of the hand-held surgical instrument of FIGS. 1 and 2.

  FIG. 1 shows a hand-held electrosurgical instrument, generally designated 1, comprising a handpiece 2 and an electrode assembly 3. The handpiece 2 includes a power source, for example, a battery 4, an RF circuit 5, and a control circuit 6. The handpiece includes a hand switch 7 for giving a command to the control circuit 6. The handpiece includes a handpiece connector 8 that engages a corresponding electrode assembly connector 9 carried on the electrode assembly 3. The electrode assembly includes an elongate shaft 10 and an end effector 11 at the distal end of the shaft. In FIG. 1, in the electrode assembly, an end effector 11 includes a pair of jaws 12. Lead wires (not shown) are routed along the shaft 10 of the electrode assembly 3 to connect the RF circuit to the end effector 11 so that the jaws 12 constitute an electrode capable of coagulating tissue.

  FIG. 2 shows the handpiece 2 with another electrode assembly 3 '. The electrode assembly 3 ′ has a connector 9 ′, and the end effector 11 ′ of the electrode assembly 3 ′ includes a deployable cutting needle 13. Again, lead wires (not shown) are routed along the shaft 10 'of the electrode assembly 3' and the RF needle is connected to the end effector 11 'so that the cutting needle 13 is capable of cutting an electrode capable of cutting tissue. It is configured. Thus, as is well known in the art, both tissue cutting and coagulation are possible depending on the design of the end effector and the characteristics of the RF signal supplied to the end effector, eg, the power and frequency of the RF signal.

  The connector 9 on the electrode assembly 3 includes a resistor 14 that becomes part of the RF circuit 5 when the electrode assembly 3 is connected to the handpiece 2. Resistor 14 in electrode assembly 3 of FIG. 1 has a different value than resistor 14 'of electrode assembly 3' of FIG. This means that when the hand switch 7 is used to activate the instrument of FIG. 1, the resistor 14 changes the RF output reaching the jaw 12 to an RF output compatible with tissue coagulation. On the other hand, when the hand switch 7 is used to activate the instrument of FIG. 2, the resistor 14 'changes the RF power reaching the cutting needle 13 to make it suitable for tissue cutting. The handpiece 2 can produce the same RF output in either case if necessary, but this change is not made in the handpiece 2. Instead, it is resistors 14 and 14 'that change the output to suit the respective use of each instrument. This keeps the handpiece design as simple as possible, which is a great advantage for handheld devices where both weight and cost are significant concerns.

  FIG. 3 shows the control circuit 6 of the RF circuit 5. The control circuit typically includes a signal generator 15 that generates a sawtooth waveform 16 generated by integrating the amplified current signal. This sawtooth waveform is input to the comparator 17, and the output is used to control the RF circuit 5. FIG. 4 shows the operation of the comparator 17 in which the sawtooth waveform 16 is compared with the threshold voltage 18. The threshold voltage is set by a circuit such as a voltage divider made of the resistor 14, and the level of the threshold voltage 18 is determined depending on the value of the resistor 14. FIG. 4 shows how the sawtooth waveform 16 is compared to the threshold 18 to generate a square wave 19. Here, the mark-to-space ratio (or duty cycle) of the square wave 19 is set by the threshold value 18. This square wave 19 is used to control the RF circuit. The RF circuit is “on” when the square wave is at a high level and “off” when the square wave is at a low level. Therefore, the power intensity of the RF energy supplied to the electrode assembly 3 depends on the mark-to-space ratio (duty cycle) of the square wave 19 and thus on the resistor 14.

  FIG. 5 shows the effect of a higher value resistor 14 'resulting in a higher threshold 18'. The comparator produces a square wave 19 'that is similar to the square wave of FIG. 4, but with a smaller mark-to-space ratio (duty cycle). Accordingly, the power of the RF energy supplied to the electrode assembly 3 ′ is reduced as compared with the electrode assembly 3.

  FIG. 6A shows an alternative embodiment in which the connector 8 on the handpiece 2 comprises a primary coil 20 and the connector 9 on the electrode assembly 3 comprises a secondary coil 21. When the electrode assembly 3 is connected to the handpiece 2, the primary coil 20 and the secondary coil 21 cooperate to form a transformer output field for the RF circuit 5. When the electrode assembly 3 ′ of FIG. 2 is connected to the handpiece, the connector 9 ′ has secondary coils 21 ′ having different turns as shown in FIG. 6B. Accordingly, the RF output reaching the end effector 11 is different from the RF output reaching the end effector 11 '. This is true even if the base RF output generated by the handpiece is the same in both cases.

  In this way, the effect of the secondary coil is different in each case, so that the voltage of the RF output supplied to the end effectors 11 and 11 'is different. Thus, the RF power can be adapted to the particular electrode assembly used with the handpiece 2 while maintaining the simplicity of the handpiece itself.

  As an alternative to the primary coil 20 in the handpiece and the secondary coil 21 in the electrode assembly, both the primary and secondary coils can be placed in the electrode assembly. In that case, the connection between the electrode assembly and the handpiece can be a very direct, simply power line that supplies power to the primary coil 20 in the electrode assembly.

  Those skilled in the art will customize the output from the handpiece to match the target electrode assembly, even if the components in both electrode assemblies are resistors, transformers, secondary coils, or other components. You will understand that it can be changed. Components can be RF energy power, voltage or current, RF energy frequency, or RF energy type (continuous burst or pulsed burst, signal shape (eg, square wave, sine wave, sawtooth, etc.), or duty cycle) Any one or more of a plurality of parameters relating to the output from the handpiece can be changed. Thus, in general, embodiments of the present invention comprise at least one common or standard RF output signal, ie, a handpiece that provides an RF output signal at a defined frequency and power and / or amplitude; At least one electrode assembly configured to engage the handpiece and receive an RF output signal from the handpiece and to adapt it to the specific signal required by each electrode assembly. As described above, in the embodiments of the present invention, it is a component such as a step-up transformer or a step-down transformer that is responsible for adaptation, or one or more passive components having a resistance characteristic or a reactive characteristic. Or other signal conversion means having a necessary transmission function.

  Further modifications, additions, removals or substitutions to provide further embodiments will be apparent to those skilled in the art, any and all of which will be encompassed by the appended claims.

DESCRIPTION OF SYMBOLS 1 Hand-held electrosurgical instrument 2 Handpiece 3, 3 'Electrode assembly 4 Battery 5 RF circuit 6 Control circuit 7 Hand switch 8 Handpiece connector 9, 9' Electrode assembly connector 10 Shaft 11, 11 'End effector 12 Jaw 13 Cutting needle 14, 14 'resistor 15 signal generator 16 sawtooth waveform 17 comparator 18 threshold 19, 19' threshold 20 primary coil 21, 21 'secondary coil

Claims (14)

A hand-held electrosurgical instrument comprising a handpiece and an electrode assembly, wherein the electrode assembly includes one or more electrodes and a connector that allows the electrode assembly to be attached to and detached from the handpiece. The handpiece is
a) a battery;
b) an RF oscillator circuit for generating radio frequency output;
c) switching means operable by a user of the electrosurgical instrument;
d) a control circuit for controlling the radio frequency output, the control circuit receiving a signal from the switching means and correspondingly supplying one or more radio frequency outputs to the electrode assembly;
The electrode assembly captures a radio frequency output coming out of the handpiece, and a component that can be changed so that the radio frequency output reaching the one or more electrodes is different from the radio frequency output coming out of the handpiece. Including;
Hand-held electrosurgical instrument. The component capable of changing the RF output reaching the one or more electrodes comprises a transformer including at least a primary coil and a secondary coil;
The electrosurgical instrument according to claim 1. When the handpiece includes a primary transformer coil, the electrode assembly includes a secondary transformer coil, and the electrode assembly is connected to the handpiece, the primary coil and the secondary coil are connected and the RF Acts as a transformer to change the radio frequency output from the oscillator circuit;
The electrosurgical instrument according to claim 1. The electrode assembly includes a passive electrical component having a finite non-zero value parameter, wherein the passive electrical component modifies the radio frequency output reaching the one or more electrodes and is desired at the one or more electrodes. To generate a radio frequency of
The electrosurgical instrument according to any one of claims 1 to 3. The passive electrical component operates in conjunction with the control circuit to change the radio frequency output reaching the one or more electrodes;
The electrosurgical instrument according to claim 4. The passive electrical component is a resistor;
The electrosurgical instrument according to claim 4 or 5. An electrosurgical system comprising a handpiece and a plurality of electrode assemblies;
The electrode assembly is at least a first type or a second type of electrode assembly, each including one or more electrodes, removably connectable to the handpiece, the handpiece comprising:
a) a battery;
b) an RF oscillator circuit for generating radio frequency output;
c) switching means operable by a user of the electrosurgical instrument;
d) a control circuit for controlling the radio frequency output, comprising a control circuit capable of receiving a signal from the switching means and correspondingly supplying one or more radio frequency outputs to the electrode assembly;
The first type electrode assembly includes a first part, the second type electrode assembly includes a second part, and the first and second parts are wirelessly emerging from the handpiece. Capture frequency output and change the radio frequency output reaching one or more electrodes of the first type electrode assembly to be different from the radio frequency output reaching one or more electrodes of the second type electrode assembly it can;,
Electrosurgical system. An electrosurgical instrument comprising a handpiece and an electrode assembly releasably connectable to the handpiece;
The handpiece is
An RF signal source;
A control switch operable by a user to control the handpiece and output a radio frequency (RF) signal driven by the RF signal source;
The electrode assembly comprises:
One or more electrodes that form an end effector for treating tissue when an RF therapy signal is applied to the tissue;
Circuitry configured to receive the radio frequency signal from the handpiece and convert it to an RF therapy signal required by the end effector;
Electrosurgical instrument. The RF therapy signal is an RF cutting signal when the end effector is a cutting instrument and an RF coagulation signal when the end effector is a coagulating instrument;
The electrosurgical instrument according to claim 8. The circuitry comprises at least a secondary coil of a transformer configured to change the RF signal output from the handpiece;
The electrosurgical instrument according to claim 8 or 9. The handpiece comprises a primary coil of the transformer;
The primary coil is configured to receive a signal from the RF signal source and generate the output RF signal from the handpiece;
The electrosurgical instrument according to claim 10. The circuitry further comprises a primary coil of the transformer, the primary coil configured to receive the output RF signal from the handpiece;
The electrosurgical instrument according to claim 10. The circuitry comprises an electrical network configured to convert the radio frequency signal to the RF therapy signal;
The electrosurgical instrument according to claim 8 or 9. The electrical network is a passive network comprising one or more resistors, impedances and / or reactances;
The electrosurgical instrument according to claim 13.

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